Abbott questions PM's security credentials

OPPOSITION Leader Tony Abbott has questioned Prime Minister Julia Gillard's national security credentials ahead of a major speech she is set to deliver on the topic.

Ms Gillard will reportedly single out China and cyber attacks as key national security concerns when she delivers her first major election year speech in Canberra on Wednesday.

It is believed she will also outline Australia's national security objectives, actions and priorities over the next five years.

But Mr Abbott says the government has a credibility problem on national security.

"I think it's pretty hard for the government to be credible about national security when it's reduced defence spending as a percentage of GDP to the lowest levels since 1938," he told reporters in Brisbane.

"The world is not so safe a place that we can afford to be asleep at the wheel when it comes to defence."

But Mr Abbott is not promising a coalition government will restore defence spending to Howard government levels.

"Our aspiration is to spend two per cent of GDP on defence," he said. "That's what we need to get back to."